A new norm on the space of reproducing kernel Hilbert space operators and Berezin number inequalities

Fuente: arXiv
Enregistré dans:
Détails bibliographiques
Auteurs principaux: Nayak, Raj Kumar, Bhunia, Pintu
Format: Preprint
Publié: 2025
Sujets:
Accès en ligne:
Tags: Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
_version_ 1866912318168760320
author Nayak, Raj Kumar
Bhunia, Pintu
author_facet Nayak, Raj Kumar
Bhunia, Pintu
contents In this note, we introduce a novel norm, termed the $t-$Berezin norm, on the algebra of all bounded linear operators defined on a reproducing kernel Hilbert space $\mathcal{H}$ as $$\|A\|_{t-ber} = \sup_{ λ, μ\in Ω} \left\{ t|\langle A \hat{k}_λ, \hat{k}_μ\rangle| + (1-t) |\langle A^* \hat{k}_λ, \hat{k}_μ\rangle| \right\}, \quad t\in [0,1],$$ where $A \in \mathcal{B}(\mathcal{H})$ is a bounded linear operator. This norm characterizes those invertible operators which are also unitary. Using this newly defined norm, we establish various upper bounds for the Berezin number, thereby refining the existing results. Additionally, we derive several sharp bounds for the Berezin number of an operator via the Orlicz function.
format Preprint
id arxiv_https___arxiv_org_abs_2504_06754
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle A new norm on the space of reproducing kernel Hilbert space operators and Berezin number inequalities
Nayak, Raj Kumar
Bhunia, Pintu
Functional Analysis
47A30, 15A60, 47A12
In this note, we introduce a novel norm, termed the $t-$Berezin norm, on the algebra of all bounded linear operators defined on a reproducing kernel Hilbert space $\mathcal{H}$ as $$\|A\|_{t-ber} = \sup_{ λ, μ\in Ω} \left\{ t|\langle A \hat{k}_λ, \hat{k}_μ\rangle| + (1-t) |\langle A^* \hat{k}_λ, \hat{k}_μ\rangle| \right\}, \quad t\in [0,1],$$ where $A \in \mathcal{B}(\mathcal{H})$ is a bounded linear operator. This norm characterizes those invertible operators which are also unitary. Using this newly defined norm, we establish various upper bounds for the Berezin number, thereby refining the existing results. Additionally, we derive several sharp bounds for the Berezin number of an operator via the Orlicz function.
title A new norm on the space of reproducing kernel Hilbert space operators and Berezin number inequalities
topic Functional Analysis
47A30, 15A60, 47A12
url https://arxiv.org/abs/2504.06754